The Environmental Protection Agency may begin regulating carbon dioxide and five other greenhouse gases, it announced Friday after concluding the gases are a danger to public health and welfare.
"This finding confirms that greenhouse gas pollution is a serious problem now and for future generations," EPA Administrator Lisa Jackson said in a statement.
If the EPA begins regulating gases that contribute to climate change, it could affect everything from the cars people drive to their sources of electricity.
The proposed finding — the EPA must hold a public comment period before finalizing any regulations — states in part: "In both magnitude and probability, climate change is an enormous problem. The greenhouse gases that are responsible for it endanger public health and welfare within the meaning of the Clean Air Act."
Friday's announcement comes two years after a Supreme Court ruling that found the EPA has the authority to regulate carbon dioxide and other greenhouse gases.
In its report, the EPA concludes there is potential for climate change to make ozone pollution worse in some regions and that it could increase the number of days with weather conditions conducive to forming ozone.
Ground-level ozone can make it more difficult to breathe, especially for people who already have asthma or other breathing problems.
In addition to carbon dioxide, the proposed ruling will cover methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride.